How to Print a Full Scale Wiring Harness Formboard

Short answer: open the harness menu in HarnessHive, choose Export, then PDF document, select the Formboard section, keep the scale at 100% and export. If the drawing is bigger than your paper, it is split into overlapping pages that you print at 100% and tape together.

A formboard is the 1:1 drawing your technician builds the harness on. If it is not true to scale, every wire gets cut and routed against the wrong reference. This guide shows how to get an accurate one out of HarnessHive and onto a board.

What you need

  • A harness with a wiring view. The formboard is generated from the wiring topology.
  • A printer, or a print shop with large format paper. Any size from A5 to A0 works, and so does a custom size.
  • Tape and a ruler, if you print on sheets smaller than the drawing.

Print the formboard in six steps

  1. Lay out the formboard. Switch the editor to Manufacturing mode, which shows the Formboard next to the BOM. With Sync Formboard from wiring on, the formboard follows your finalized wiring and keeps the labels and clips you add to it.
  2. Open the export dialog. In the harness menu choose Export, then PDF document. The Export PDF dialog lists the Schematic, Wiring, Formboard and BOM sections. The Formboard option is disabled while the view is empty.
  3. Keep the scale at 100%. The Formboard section shows the total formboard size at the chosen scale. At 100% that is the real size of the harness on the board. Only change it for a smaller draft or review copy.
  4. Choose the sheet size. Pick A5 to A0, or enter a custom paper width and height. New sections start on A4 landscape. When the drawing is larger than one sheet, HarnessHive tiles it over several pages. The preview has a tile minimap, so you can jump to any page by its row and column. Sizes, margins and the formboard dimensions follow your workspace's engineering units, so US teams work in inches and everyone else in millimetres.
  5. Set margin and overlap. The print margin keeps the drawing inside what your printer can reach, 10 mm by default. The overlap repeats part of the printable area on neighboring sheets, 10% by default, and adjoining page labels tell you which sheet goes next to which.
  6. Export and print at 100%. Choose Export section for just the formboard, or Export all sections to include the rest. Then print the PDF at 100%. Turn off fit to page and scale to fit in the print dialog.

Check the scale before you build

Measure a known distance on the printed sheet with a ruler, such as the length of a branch from the drawing. If it matches, the print is full scale. If it is short, your printer or viewer scaled the page. Print again at 100%.

For a multi page print, align the sheets using the overlap and the adjoining page labels, then tape them together before laying out wires.

Common mistakes

  • Fit to page is on. It silently shrinks the drawing. This is the most common cause of a formboard that is not 1:1.
  • The wiring changed after the last export. Export again. The PDF is a snapshot of the formboard at that moment.
  • Margins cut the drawing. Raise the print margin if your printer cannot reach the edge of the paper.
  • A browser that cannot keep mixed paper sizes. If the dialog says so, download the PDF instead of printing straight from the browser.

Next, see how a team works on the same harness at once, or read why we built HarnessHive.

FAQ

What is a wiring harness formboard?

A formboard, also called a nailboard or build board, is a full size drawing of the harness. Technicians lay wires and connectors on top of it, so lengths and branch positions come out right without measuring each one.

Can I print a full scale formboard on a normal A4 printer?

Yes. When the drawing is larger than the sheet, HarnessHive splits it across several pages with an overlap and labels for the adjoining pages. Print them at 100% and tape them together.

What scale does HarnessHive use for the formboard PDF?

A new PDF section starts at 100%, which is 1:1. You can change the scale for a smaller draft, but only a print at 100% of a 100% PDF is full scale.

Does the formboard update when I change the wiring?

Yes, when Sync Formboard from wiring is on. The formboard follows finalized wiring and keeps the manufacturing only items you added, such as labels and clips.

Which paper sizes can I export to?

A5, A4, A3, A2, A1 and A0, or a custom width and height. Pick the size your printer or print shop handles.

Does the export support US measurements?

Yes. The export dialog follows the engineering units set for your workspace, so paper size, margin and formboard size are shown in millimetres or in inches.

Try it on your next harness

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